Yujuan Zhang1,2, Donghua Li1, Rong Zhou1, Xiao Wang1, Komivi Dossa1,3, Linhai Wang1, Yanxin Zhang1,
Jingyin Yu1, Huihui Gong2, Xiurong Zhang1* and Jun You1*
Background : Soil salinity is one of the major serious factors that affect agricultural productivity of almost all crops
worldwide, including the important oilseed crop sesame. In order to improve salinity resistance in sesame, it is
crucial to understand the molecular mechanisms underlying the adaptive response to salinity stress.
Results : In the present study, two contrasting sesame genotypes differing in salt tolerance were used to decipher
the adaptive responses to salt stress based on morphological, transcriptome and metabolome characterizations.
Morphological results indicated that under salt stress, the salt-tolerant (ST) genotype has enhanced capacity to
withstand salinity stress, higher seed germination rate and plant survival rate, as well as better growth rate than the
salt-sensitive genotype. Transcriptome analysis revealed strongly induced salt-responsive genes in sesame mainly
related to amino acid metabolism, carbohydrate metabolism, biosynthesis of secondary metabolites, plant hormone
signal transduction, and oxidation-reduction process. Especially, several pathways were preferably enriched with
differentially expressed genes in ST genotype, including alanine, aspartate and glutamate metabolism, carotenoid
biosynthesis, galactose metabolism, glycolysis/gluconeogenesis, glyoxylate and dicarboxylate metabolism, porphyrin
and chlorophyll metabolism. Metabolome profiling under salt stress showed a higher accumulation degree of
metabolites involved in stress tolerance in ST, and further highlighted that the amino acid metabolism, and sucrose
and raffinose family oligosaccharides metabolism were enhanced in ST.
Conclusions : These findings suggest that the candidate genes and metabolites involved in crucial biological
pathways may regulate salt tolerance of sesame, and increase our understanding of the molecular mechanisms
underlying the adaptation of sesame to salt stress.
Keywords :Keywords : Salt stress, Sesame, Transcriptome, Metabolome, Metabolic pathway, Amino acid, Raffinoseloci.